Cross brace for a tabletop



FIG. 1 is a perspective view of a cross brace for a tabletop showing my new design;

FIG. 2 is a side elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is an end elevation view thereof. 

CLAIM The ornamental design for a cross brace for a tabletop, as shown and described. 